The size and shape of rhodopsin solubilized in several detergents is to be determined by hydrodynamic methods. These include transient electric birefringence, viscosity, and sedimentation velocity studies. Transient birefringence yields two distinct rotary diffusion coefficients, which determine the dimensions of the two axes of the equivalent hydrodynamic ellipsoid of revolution for macromolecules in solution. Determining the size and shape of rhodopsin-detergent micelles, the detergent micelles, and the number of moles of detergent bound per mole of rhodopsin, will allow the structure of the rhodopsin core of the micelles to be inferred. The agreement of such structures with the hydrodynamic parameters, sedimentation coefficient and intrinsic viscosity will provide a test of consistency with respect to inferred structure. Binding studies will be based on equilibrium dialysis of rhodopsin with labelled detergents. The effect of bleaching with white light will be studied in each detergent to determine whether conformational changes due to bleaching are detergent dependent or not.